Finding the Fourth Proportional to 378,918, 522,906.89 and 209,152.17

Step by Step Solution

1. Step 1: Write the proportion equation
   378,918 : 522,906.89 = 209,152.17 : x
2. Step 2: Convert to fraction form
   378,918/522,906.89 = 209,152.17/x
3. Step 3: Cross multiply
   378,918x = 522,906.89 × 209,152.17
4. Step 4: Simplify right side
   378,918x = 109,367,109,705.69
5. Step 5: Solve for x
   x = 109,367,109,705.69/378,918
6. Step 6: Final answer
   x = 288,630.02